A person can absorb vitamin D through sunlight, but most people aren’t outside enough to get the recommended amount. Doctors say the easiest way to boost levels is with supplements. Dr. Lane says if your levels are low heading into surgery, you can start taking supplements even at that point and your levels will likely improve by the time bone is actually beginning to heal two to four weeks later.

“I don’t think it makes much difference in the first two to four weeks because bone is preparing to heal,” Dr. Lane says. “If you can recognize it you can pretty much correct it within two to four weeks and that’s the time you’ll need it.”

Dr. Lane says people should consult with their doctor, but he says 2,000-4,000 milligrams of vitamin D a day should correct levels for most people.

“That doesn’t mean you can make people heal by putting them on vitamin D,” Dr. Lane explains. “But in the absence of vitamin D there will be people who don’t heal following fractures. Assuming you do good surgery and don’t get infected, the overwhelming cause of failure to heal is low vitamin D.”

Mark Spangehl, MD, works in the department of orthopaedic surgery at the Mayo Clinic in Arizona and has doubts about this study.

“There is no evidence in that study that the vitamin D deficiency has actually had an impact, positive or negative, on recovery,” Dr. Spangehl says. “Any correlation to recovery, or damaging patient recovery, or having any influence at all on patient recovery is purely speculative.”

Dr. Spangehl says the study is useful for raising awareness and addressing the problem of vitamin D deficiency in the general population. But he says further study is needed to draw any conclusions beyond that.

“The next step would be to see if certain levels of deficiency actually have a correlation to a negative outcome in specific groups of surgical patients,” Dr. Spangehl says. “Vitamin D deficiency may certainly be a problem in the general population relating to osteoporosis with subsequent fragility fractures, but again there is nothing in this [study] that suggests that patient recovery after surgery is being damaged by the levels of vitamin D deficiency noted.”